1. Field of the Invention
The present invention relates to an electrical connector for electrically connecting an electronic package such as a central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB), and particularly to an electrical connector with a strengthened actuation device that actuates connection and disconnection of the CPU with and from the electrical connector.
2. Description of Prior Art
Electrical connectors are widely used in personal computer (PC) systems for electrically connecting electronic packages such as CPUs with circuit substrates such as PCBs. Typical such electrical connectors are known as CPU sockets. A typical CPU socket comprises a base soldered and electrically connected with the PCB, a cover slidably mounted on the base and having a CPU attached thereon, and an actuation device for actuating the cover to slide along the base.
The CPU has a multiplicity of pins depending from a bottom surface thereof and arranged in a rectangular array. The cover of the CPU socket has a multiplicity of through holes arranged in a rectangular array corresponding to the pins of the CPU. The base of the CPU socket has a multiplicity of passageways arranged in a rectangular array corresponding to the pins of the CPU. Each passageway receives an electrical terminal therein.
In use, the CPU is attached to the CPU socket. The pins of the CPU extend through the corresponding through holes of the cover and are received in the corresponding passageways of the base. The pins of the CPU do not contact the corresponding electrical terminals. Thus the CPU is attached with zero insertion force. In particular, the pins of the CPU are prevented from being flexed by sudden force being applied thereto by the electrical terminals. Then, the actuation device actuates the cover to slide along the base. When the cover reaches a closed position with respect to the base, the actuation device pushes the pins of the CPU into mechanical and electrical engagement with the corresponding electrical terminals.
This kind of conventional CPU socket is detailed in xe2x80x9cDevelopment of a ZIF BGA Socketxe2x80x9d (pp16xcx9c18, May 2000, Connector Specifier Magazine). Similar kinds of CPU sockets are also disclosed in Taiwan Patent Issue Nos. 394472, 481375, 481378, 443622, and 462542.
Taiwan Patent Issue Nos. 394472, 481375, 481378, 443622 and 462542 each disclose a CPU socket comprising an actuation device positioned between a base and a cover. The actuation device comprises a camshaft for actuating the cover to slide along the base, and an operation lever extending perpendicularly from one end of the camshaft to facilitate manual handling by a user. During an opening process, actuating portions of the camshaft are at work at the same time; and during a closing process, the same actuating portions are also at work at the same time. This results in diameters of the actuating portions being much smaller than diameters of other portions of the camshaft. Accordingly, a total tension of the camshaft is reduced, and the camshaft is prone to distort.
Furthermore, when the CPU is attached on or removed from the CPU socket, the operation lever is rotated upwardly to a position perpendicular to the base. At this position, the operation lever is blocked from further rotation by a stop provided at a side of the base. However, the operation lever is still prone to be accidentally rotated beyond said perpendicular position. When this happens, the CPU socket may be damaged.
A new electrical connector that overcomes the above-mentioned disadvantages is desired.
Accordingly, an object of the present invention is to provide an electrical connector for electrically connecting an electronic package such as a CPU with a circuit substrate such as a PCB, the electrical connector having a strengthened actuation device.
Another object of the present invention is to provide an electrical connector configured to help prevent an actuation device thereof from being over-rotated.
To achieve the above-mentioned objects, an electrical connector in accordance with a preferred embodiment of the present invention is for electrically connecting a CPU with a PCB. The electrical connector comprises a generally rectangular insulative base, a cover slidably attached on the base, and an actuation device for actuating the cover to slide along the base.
The actuation device comprises a camshaft and an operation lever. The camshaft is positioned between the base and the cover, and the operation lever extends perpendicularly from one end of the camshaft. The operation lever is positioned substantially outside the base and the cover, to facilitate manual handling by a user. The camshaft comprises first actuating portions, a central second actuating portion and outmost supporting portions. The base comprises outmost first locating portions, second locating portions and a central third locating portion, respectively receiving the supporting portions, the first actuating portions and the second actuating portion of the camshaft. During a closing process, the first actuating portions are at work; and during an opening process, the second actuating portion is at work. This ensures that diameters of the different portions of the camshaft are different. Thus the camshaft can have sufficiently high tension to minimize the risk of it being distorted.
Furthermore, when the operation lever is rotated to a position perpendicular to the base, the first actuating portions are engaged with second flat side walls of the second locating portions of the base. This helps prevent the operation lever from being rotated beyond said perpendicular position and causing damage to the electrical connector.
Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which: